Cassette of cassette type stapler

The present application is a continuation of, and claims priority of, U.S. Ser. No. 10/540,738, presently pending, which was the US national phase of PCT/JP03/17039, filed 26 Dec. 2003.

The present invention relates to a cassette to be used in a cassette type stapler and to a holder structure to be used in said cassette.

As the cassette for the cassette type stapler of the prior art, there are a cassette disclosed in JP-A-62-218080 and a cassette disclosed in JP-A-6347076. A cassette 80 (FIG. 59 to FIG. 61) disclosed in JP-A-62-218080 widely spreads in the market. Not only a holder member 81 but also a feeder device 82 and a rod structure 86 (FIG. 60) are essential in the cassette 80. The holder member 81 is formed into a box shape having its back wall removed, and a cap 87 of the rod structure 86 functions as the back wall of the holder member. Specifically, the assembly of the cassette 80 is completed by mounting staples 84 and the feeder device 82 in the recited order from the back of the holder member 81, by mounting a rod 88 of the rod structure 86 having a spring 85 attached thereto, and by integrating the rod structure 86 and the holder member 81 so that an engaging projection 89 of the rod structure 86 snugly in the hole 90 of the cassette. Thus, the cassette 80 is mounted in the single action and is assembled easily to some extent. In the course of the mass production, however, many labors are required for fitting the engaging projection of the rod structure in the hole of the cassette.

The cassette, as manufactured under the trade name of “CSV” by e-TOP Co., Ltd., for the cassette type stapler of the prior art is commercially available (FIG. 62 to FIG. 64). Not only the holder member but also a feeder 95 and a rod structure 93 are essential for the cassette of the trade name “CSV”. The holder member is completed with a plurality of members. Specifically, the holder member body is formed into a box shape having its bottom and back removed, and a holder member bottom wall 92 or a member different from the holder member body is fitted on the bottom of the holder member body whereas the rod structure 93 is fitted on the back of the holder member body. A spring 96 is attached to a rod 94 of the rod structure 93. In short, this cassette requires the numerous members, and its manufacture takes many labors in the mass production procedure.

In this invention, the mechanism to function as the outer case and the mechanism for guiding the staples are integrated.

In the invention, moreover, even at the mechanism to function as the outer box, the back wall or the bottom wall is not a separate member but is made integral. In other words, the two members essential for the cassette disclosed in IP-A-62-218080, that is, the holder 81 and the rod structure 87 are made of one member. In the invention, moreover, as the mechanism for guiding the staples, there is adopted not the mechanism, in which the spring is fitted on the rod-shaped member, but the structure, in which the spring engages directly at its one end with the holder body and at its other end with the feeder and in which the staples are guided to a predetermined position as they are driven. These structures need the member for bringing the spring into engagement with the holder body and the staple guide member. These members are also integrated with the holder.

In the invention, moreover, all of the mechanism to function as the outer case and the mechanism for guiding the staples are integrally molded by using one set of molds, while eliminating any of glue, weld and screws.

There is provided a holder structure to be used as a cassette of a cassette type stapler, comprising: a holder member including a top side portion, a bottom side portion, a right side portion, a left side portion, a front side portion and a back side portion; and a staple guide member extending in the inside of said holder member in the axial direction of said holder member, wherein, in case the sections of X-Y directions of a portion forming said top side portion, a portion forming said bottom side portion, a portion forming said right side portion, a portion forming said left side portion, a portion forming said front side portion, a portion forming said back side portion and a portion forming said staple guide member are projected in one virtual plane in the X-Y directions, the section of one portion in the X-Y directions and the section of another portion in the X-Y directions are absent over each other in a Z-direction.

The cassette according to the invention is one to be used in the cassette type stapler. This cassette type stapler is used by mounting the cassette precharged with the staples in the stapler body.

The holder structure according to the invention has a holder member. This holder member is formed into a hexahedron composed of a top side portion, a bottom side portion, a right side portion, a left side portion, a front side portion and a back side portion. In connection with these top, bottom, right, left, front and back side portions, the prior art structure does not need any hole for driving the staples on principle, excepting the hole for the blade and the staple to pass through. For the structure to be integrally molded, however, the invention is provided with a number of holes in the top side portion and the bottom side portion. The locations of the holes have an important meaning in the invention, as will be described hereinafter.

The holder member functions as the outer box for housing the staples or the like.

The holder structure according to the invention has the staple guide member. This staple guide member extends in the holder member in the axial direction of the holder member. The staples engage with the staple guide in the holder. The staples move forward, when driven, and hence the staple guide extends in the axial direction of the holder member.

The mode of the staple guide is sufficient if it can engage with the staples and can guide their axial movements. The staple guide may be located either at a position for supporting the top backs of the staples or at a position for supporting the leading ends of the legs of the staples.

Herein: the X-direction means the longitudinal axis of the cassette; the Y-direction means the transverse axis of the cassette; and the Z-direction means the vertical axis of the cassette. The X-Y directions means the directions parallel to the X-Y plate (i.e., the plane defined by the X-axis and the Y-axis. The section in the X-Y directions means the section, which is cut in a plane parallel to the X-Y plate (i.e., the plane defined by the X-axis and the Y-axis).

In the holder structure according to the invention, in case the sections of X-Y directions of the portion forming the top side portion, the portion forming the bottom side portion, the portion forming the right side portion, the portion forming the left side portion, the portion forming the front side portion, the portion forming the back side portion and the portion forming the staple guide member are projected in one virtual plane in the X-Y directions, the section of one portion in the X-Y directions and the section of another portion in the X-Y directions are absent over each other in the Z-direction. As a result, it is possible to mold the cassette integrally. Specifically, the holder member and the staple guide member are made by a set of molds.

The state, in which the sections in the X-Y directions are absent over each other in the plus Z-axis direction in case the sections of all portions in the X-Y directions are projected in one virtual plane in the X-Y directions, means that the structure equipped with the holder member and the staple guide member is made by one set of molds when the cassette is to be manufactured. For this structure, of the six sides composing the holder member, the top side and the bottom side are individually provided many holes. The mold parts are parted in the Z-direction. As a result, the portions of the individual components in the sections in the X-Y directions cannot overlap in the mold parting direction. In case the top side of the holder and the bottom side of the holder are projected in one virtual plane in the X-Y directions, for example, the portions of the holes of the top side form the no-hole portions of the bottom side, whereas the portions of the holes of the bottom side form the no-hole portions of the top side.

There is provided a holder structure to be used as a cassette of a cassette type stapler, comprising: a holder member including a top side portion, a bottom side portion, a right side portion, a left side portion, a front side portion and a back side portion; and a holder spring engaging member, wherein, in case the sections of X-Y directions of a portion forming said top side portion, a portion forming said bottom side portion, a portion forming said right side portion, a portion forming said left side portion, a portion forming said front side portion, a portion forming said back side portion and a portion forming holder spring engaging member are projected in one virtual plane in the X-Y directions, the section of one portion in the X-Y directions and the section of another portion in the X-Y directions are absent over each other in a Z-direction.